Jeffrey D. Karpicke and Janell R. Blunt report that using tests to measure your comprehension of a subject also has the side benefit of helping you remember the material better. The NY times has an excellent article summarizing the findings.
Through the Microscope has dozens of concept quizzes throughout the text that help you to check your understanding of the material. Each chapter also has an end of chapter quiz to further cement the concepts. As you use this text, make sure you take advantage of theses tools.